SpriteKit Lagging on iPhone 5 but not on iPhone 6 - ios

Question

I have been working on my first SpriteKit game that perfectly works on iPhone 6 but not on iPhone 5 (iOS 8.2 on both, written in Swift). I explain my problem: there is a simple ball (a SkShapeNode) that bounces when tapping on the screen. The move is very smooth on iPhone 6 but it has some lagging on iPhone 5 but NOT the first time. The FPS is 60 all the time. I have simplified my project a maximum and I have tried everything, I really need your help so much, I am a little bit desperate. I am ready to try anything, any help would be very appreciated. Thank you so much in advance!
Here is the video (smooth the first time then lagging):
https://www.youtube.com/watch?v=xNxp2uGIJew
Here is the repository if you want to test it:
https://github.com/jonmars8/SpriteKit-Lag-iPhone5
Here is the code in the GameScene: (empty but it was the menu before simplification)
import SpriteKit
class GameScene: SKScene {
var viewController:GameViewController?
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
viewController?.presentPlayScene()
}
}
Here is the code in the PlayScene:
import SpriteKit
let PlayerCategory: UInt32 = 1 << 2
let ObstacleCategory: UInt32 = 1 << 3
class PlayScene: SKScene, SKPhysicsContactDelegate {
let world = SKNode()
var player : SKShapeNode!
var firsttap = true
var viewController : GameViewController?
override func didMoveToView(view: SKView) {
physicsWorld.gravity = CGVectorMake(0.0, -9.8)
physicsWorld.contactDelegate = self
self.createPlayer()
let obstacle = SKSpriteNode(color: SKColor.whiteColor(), size: CGSizeMake(100.0, 38.0))
obstacle.position = CGPointMake(frame.size.width / 2.0, CGRectGetMidY(frame) * 0.75 + 400)
let body = SKPhysicsBody(rectangleOfSize: obstacle.size)
body.categoryBitMask = ObstacleCategory
body.contactTestBitMask = PlayerCategory
body.collisionBitMask = PlayerCategory
body.linearDamping = 0.0
body.angularDamping = 0.0
body.dynamic = false
obstacle.physicsBody = body
self.addChild(world)
self.world.addChild(obstacle)
self.world.addChild(player)
}
func createPlayer() {
self.player = SKShapeNode(circleOfRadius: 13)
player.fillColor = SKColor.greenColor()
player.strokeColor = SKColor.blackColor()
player.lineWidth = 1
let body = SKPhysicsBody(circleOfRadius:13)
body.dynamic = false
body.linearDamping = 0.0
body.angularDamping = 0.0
body.allowsRotation = false
body.affectedByGravity = true
body.categoryBitMask = PlayerCategory
body.contactTestBitMask = ObstacleCategory
body.collisionBitMask = ObstacleCategory
player.physicsBody = body
player.position = CGPointMake(CGRectGetMidX(frame), CGRectGetMidY(frame) * 0.75)
}
override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
for touch: AnyObject in touches {
if firsttap {
player.physicsBody?.dynamic = true
firsttap = false
}
let touchLoc = touch.locationInNode(self)
var right = true
if touchLoc.x > CGRectGetMidX(frame) {
right = false
}
player.physicsBody?.velocity = right ?
CGVectorMake(CGFloat(-65), CGFloat(650)) :
CGVectorMake(CGFloat(65), CGFloat(650))
}
}
override func update(currentTime: NSTimeInterval) {
var pos = -player.position.y + CGRectGetMidY(frame)
if pos < world.position.y {
world.position = CGPointMake(world.position.x, pos)
}
}
func didBeginContact(contact: SKPhysicsContact) {
viewController?.presentGameScene()
}
}
Here is the code in the gameViewController:
extension SKNode {
class func unarchiveFromFile(file : NSString) -> SKNode? {
if let path = NSBundle.mainBundle().pathForResource(file, ofType: "sks") {
var sceneData = NSData(contentsOfFile: path, options: .DataReadingMappedIfSafe, error: nil)
var archiver = NSKeyedUnarchiver(forReadingWithData: sceneData!)
archiver.setClass(self.classForKeyedUnarchiver(), forClassName: "SKScene")
if file == "GameScene"{
let scene = archiver.decodeObjectForKey(NSKeyedArchiveRootObjectKey) as GameScene
archiver.finishDecoding()
return scene
}
else {
let scene = archiver.decodeObjectForKey(NSKeyedArchiveRootObjectKey) as PlayScene
archiver.finishDecoding()
return scene
}
} else {
return nil
}
}
}
class GameViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
self.presentGameScene()
}
func presentPlayScene() {
if let scene = PlayScene.unarchiveFromFile("PlayScene") as? PlayScene {
// Configure the view.
let skView = self.view as SKView
skView.showsFPS = true
skView.showsNodeCount = true
/* Sprite Kit applies additional optimizations to improve rendering performance */
skView.ignoresSiblingOrder = true
/* Set the scale mode to scale to fit the window */
scene.scaleMode = .AspectFill
//reference to self
scene.viewController = self
skView.presentScene(scene, transition: SKTransition.crossFadeWithDuration(0.5))
}
}
func presentGameScene() {
if let scene = GameScene.unarchiveFromFile("GameScene") as? GameScene {
// Configure the view.
let skView = self.view as SKView
skView.showsFPS = true
skView.showsNodeCount = true
skView.showsQuadCount = true
skView.showsDrawCount = true
/* Sprite Kit applies additional optimizations to improve rendering performance */
skView.ignoresSiblingOrder = true
/* Set the scale mode to scale to fit the window */
scene.scaleMode = .AspectFill
//reference to self
scene.viewController = self
skView.presentScene(scene, transition: SKTransition.crossFadeWithDuration(0.5))
}
}
override func shouldAutorotate() -> Bool {
return true
}
override func supportedInterfaceOrientations() -> Int {
if UIDevice.currentDevice().userInterfaceIdiom == .Phone {
return Int(UIInterfaceOrientationMask.Portrait.rawValue)
} else {
return Int(UIInterfaceOrientationMask.All.rawValue)
}
}
override func prefersStatusBarHidden() -> Bool {
return true
}
}
Note: on iPhone 6 there is a very small lagging when quickly tapping on the screen at the very first beginning of the game.
I have replaced the SKShapeNode by SKSpriteNode and it hasn't changed anything.
Please help me, thank you so much in advance!

Answer 1

I posted my view controller code over here. I do not observe performance difference between iPhone 5 and iPhone 6. Can you try my code and let me know if the lag is still there?
import UIKit
import SpriteKit
class GameViewController: UIViewController
{
var playScene: PlayScene?
override func viewDidLoad() {
}
override func viewDidAppear(animated: Bool) {
let view = self.view as SKView
playScene = PlayScene(size: view.bounds.size)
playScene!.viewController = self
view.showsFPS = true
view.showsNodeCount = true
view.presentScene(playScene!)
}
func presentGameScene()
{
let view = self.view as SKView
playScene = PlayScene(size: view.bounds.size)
playScene!.viewController = self
view.presentScene(playScene!)
}
}

Answer 2

Maybe you can try to apply impulse instead of changing velocity directly:
if(right){
player.physicsBody?.velocity = CGVectorMake(0,0)
player.physicsBody?.applyImpulse(CGVectorMake(-3, 15))
}else{
player.physicsBody?.velocity = CGVectorMake(0,0)
player.physicsBody?.applyImpulse(CGVectorMake(3, 15))
}
Also I can't produce that lag with your code(but only tested on iPhone 6)...Try to experiment with update vs didSimulatePhysics though. And try to isolate the part which causing the lag. Delete the code from update method to see what causing the lag (ball bouncing or moving the world node or something else).